821841980 has 24 divisors (see below), whose sum is σ = 1800906912. Its totient is φ = 314443712.

The previous prime is 821841919. The next prime is 821841983. The reversal of 821841980 is 89148128.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (821841983) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 892847 + ... + 893766.

It is an arithmetic number, because the mean of its divisors is an integer number (75037788).

Almost surely, 2^821841980 is an apocalyptic number.

It is an amenable number.

821841980 is an abundant number, since it is smaller than the sum of its proper divisors (979064932).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

821841980 is a wasteful number, since it uses less digits than its factorization.

821841980 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1786645 (or 1786643 counting only the distinct ones).

The product of its (nonzero) digits is 36864, while the sum is 41.

The square root of 821841980 is about 28667.7864509976. The cubic root of 821841980 is about 936.6904817564.

The spelling of 821841980 in words is "eight hundred twenty-one million, eight hundred forty-one thousand, nine hundred eighty".